1. Field of the Invention
The present invention generally relates to the mounting of windows in a frame, particularly to the mounting of windows of a vehicle, e.g. an automobile, in the body frame work. The invention provides a window ready to be mounted comprising, along its edges, a first profiled bead of adhesive material, already cured and having the general cross section of an U-profile. This first bead is elastic but not plastically deformable. The first bead is adapted to receive in its interior a second bead of plastically deformable not yet cured adhesive material consisting of a substance chemically compatible to the material of the first bead. Further, the invention relates to a method of manufacturing a vehicle window of the kind mentioned above.
2. Prior Art
Conventionally, a vehicle window is fixed in the frame of a vehicle body by means of a double U-profile frame member made of rubber or a similarly elastically resilient material. On the one hand, the edge of the window is received in a first recess of the double U-profile facing the interior of the double U-profile frame member, and on the other hand, the second recess directed away from the double U-profile frame member engages the edges of a body frame, of a flange or the like of the vehicle body to thereby fix the window in its desired position.
More and more, to so-called direct mounting of vehicle windows is used in which an edge portion of the window is glued to the edges of a body frame, of a flange or the like e.g. of a vehicle body by means of a suitable adhesive material. The known methods may be divided into the following three groups:
1. Methods in which the window is delivered to the car manufacturer in a "pure" form, in some cases equipped with a layer of material along its edges which is impermeable to light and UV-radiation and/or with a layer of primer material. No further preparation of the window glass has been effected. Thereby, the mounting adhesive material is applied immediately in situ, i.e. just before mounting the window into the car body by gluing.
2. Methods in which the window is provided with a first bead of adhesive material, if appropriate also using a light- or UV-impermeable layer and/or a primer layer. The application of this first bead is performed separatly from the car manufacturing plant or from the assembling line. The first bead is fully cured. The real mounting material is again applied immediately prior to mounting the window into the frame of the car body.
3. Methods in which the window is fully prepared, ready to be mounted, distantly from the assembling line and probably some time prior to having to be mounted. Thereby, the adhesive bead required for gluing the window into the frame of the car body, consisting of a polyurethane material curing under the influence of moisture, is applied along the edges of the window, and the window thus prepared, ready to be mounted, is sealed in air tight foil material to enable the window to be stored during a certain period without curing of the adhesive material.
All three methods mentioned hereinabove can not provide an optimal solution. The reason is that in all cases considerable time- and labour-consuming operations have to be performed to prepare the window for mounting. These operations have to be done immediately in situ, e.g. at the assembly line for an automobile. Particularly, in the case of the methods 1. and 2. explained hereinbefore, the window probably has to be cleaned along its edge portion and the adhesive material must be applied to the window and/or to the edge portion of the frame, of the flange or the like of a car body. In the case of method 3. explained hereinbefore, a large sized sealing foil must be carefully removed in order not to damage the already applied adhesive material and the large and expensive sealing foil must be removed from the work place and destroyed or recycled in some way.
The purpose of the present invention is, generally speaking and in the widest sense, to improve a method of the category 3. explained hereinbefore and to provide an improved ready-to-mount vehicle window.
A method relating to the aforementioned category 1. is known, for instance, from the published German Patent Application P 27 30 831 and must not be discussed in detail here. The disadvantages of the methods according to category 1. are well known in the art; particularly disadvantageous is that the edge portion onto which the adhesive material is applied has to be cleaned just prior to applying the adhesive material, the time-consuming applying of the adhesive material bead which must be performed with the utmost accuracy and the short period of time provided to perform these operation which is directly dependent from the operation cycle set for the assembly line.
The published German Patent Application P 34 09 831 discloses a vehicle window suitable for adhesive mounting in a car body; the subject matter of that application belongs to the aforementioned category 2.
The window comprises two glass layers; the glass layer facing the interior of the vehicle is smaller than the outer glass layer such that a step-shaped recess is formed running along the edge of the window. The glass layer with the larger size comprises a frame-like strip applied to the projecting edge portion and consisting of a light-impermeable material. Onto this frame-like strip is applied a continuous bead consisting of a sealing and adhesive material filling the step-shaped recess and preventing a diffusion of steam into the space between the two glass layers. The size and shape of the aforementioned continuous bead serves as an intermediate layer for the real adhesive material required to mount the window in the mounting flange of the car body.
The continuous bead can be applied to the step-shaped recess provided in the window just in the factory, immediately after the manufacturing process of the window, and thus provides a reliable sealing of the intermediate layer provided between the two glass layers from the atmospheric moisture.
If the said continuous bead projects over the inner glas layer, it serves simultaneously as a spacer if the windows are stacked one over the other one.
The continuous bead according to the aforementioned German Patent Application P 34 09 831 is preferably covered by means of a protection foil or a corresponding protection strip made of paper which is removed immediately prior to mounting the window into the car body.
The adhesive bonding of the vehicle window with the mounting flange of the car body may be performed in different ways. Preferably, a layer or a further bead of adhesive material compatible with the material of the aforementioned continuous bead is applied onto the latter one with the result that the aforementioned continuous bead serves as an intermediate body between the window and the adhesive layer.
The method according to the published German Patent Application P 34 09 960 relates to the adhesive bonding of vehicle windows into the frame of a vehicle body whereby the adhesive material is applied directly at the assembly line; thus, this publication belongs to the aforementioned category 2. According to Lhe disclosure of this publication two beads of compatible adhesive material are applied to the window in two separate phases. In the first phase, a profiled bead of adhesive material is applied onto an edge region of the window and subsequently cured whereby one or more primer layers may be provided between said profiled bead and the surface of the window. Thus, in the second phase when the second bead is applied, the first profiled bead forms an intermediate body between the window and the second bead, said intermediated body being no longer plastically deformable.
While the profiled first bead applied onto the window is already cured when the window is to be mounted, the second bead is applied at the assembly line immediately before mounting the window.
It is admitted that certain minor advantages result from a method disclosed in the two aforementioned German Patent Applications, especially with respect to the application of the second bead of adhesive material which is the real bonding bead; however, many of the disadvantages discussed in connection with the proceeding according to category 1. hereinbefore are nevertheless existing.
The only publication known to the inventors which belongs to the aforementioned category 3., i.e. a method in which the window is prepared ready to be mounted into a car body, is the published German Patent Application P 36 38 449. According to the disclosure of this publication, the application of the adhesive material onto the window is performed independently with regard to time and place of the car to which the window has to be mounted. An adhesive material is used which cures under the influence of atmospheric moisture. The adhesive material is protected from any moisture during its application or immediately thereafter until to the moment of mounting the window into the car by a combination of a superposition of a dry protection gas with a chemical drying agent and/or a physical drying process.
The window with the applied adhesive material is singly or in groups of several units packaged in an environment free of moisture such that the adhesive material can not contact any moisture during the subsequent storage or transport.
Preferably, the window is sealed between air tight foils such that the foil have a certain distance from the adhesive material. Then, the air enclosed in this window package is evacuated and the package is filled with a protection gas. The pressure on the window and the adhesive material can correspond to the atmospheric environment pressure such that even soft parts of the package are not deformed.
In order to achieve a close fit of the foils, they can be heated during packing the window. Another possibility is to shape the foils at least in the region of the adhesive material which has to be touchless covered prior to welding the foil material. In order to prevent a slipping of the packed windows when stacked suitable projections can be provided when the foils are shaped. Vacuum-shaped hard foils can be used, but particularly if soft foils are used it may be advantageous to provide spacer members inserted into the packaging in the region of the adhesive material prior to sealing the foil. By the provision of spacers also a sliding of the windows within the packaging can be prevented.
In the place where the window is to be mounted, the still packed window must be ventilated in order to enable the foil to be removed. In order to support this operation the window packaging can comprise means for the ventilating of the packaging at a later date. For instance, suitable ventilating tubes may be provided in the packaging. The ventilating operation can be performed with air having a high humidity to displace the protection gas. If a certain time period has gone before the foil is removed the curing of the adhesive material can be accelerated.
Essential is, consequently, that the window is readily prepared by means of cleaning agents, primers and adhesive material separately with regard to time and place from the assembly line, from the repair shop or the like, and that the adhesive material is perfectly sealed against moisture.
It is true that a proceeding in line with the teaching of the aforementioned publication removes the need to apply the real mounting adhesive material bead in situ, e.g. at the assembly line. On the other hand, however, it is disadvantageous that the window prepared in accordance with the teaching of the aforementioned publication must firstly be prepared for the ventilating operation, that usually a certain time has to pass after the ventilation operation, that the unpacking of the window is cumbersome and time-consuming, and that the voluminous packaging material has to be removed from the work station and destroyed or recycled. Moreover, the aforementioned publication does not disclose how an unintentional and highly unwelcome escaping of the still pasty adhesive material over the edge of the window and/or into the viewing area of the window is avoided. Finally, there are no teachings in the aforementioned publication how a positioning or centering of the window within the frame or the mounting flange of the car body is supported or simplified.